Having the privilege to work on The Shard in London as part of the London Bridge Quarter development (£1.2 billion investment) has been one of the major highlights of my career. However, it certainly wasn’t the easiest of projects. It brought about a series of challenges that were very unique to the tower crane industry, and it took every ounce of our knowledge at Van Doorn TCC to be able to complete the job safely and on time.
Select Tower Cranes chose us for the project because of our intimate knowledge of the Comedil tower cranes being used on site. They also liked Cornelis Van Doorn’s reputation for being able to climb any crane safely and his ability to meet tight time restrictions, which were imposed on the project.
There were two cranes on this project that were never built before. The first was having a tower crane self-balance on top of a slip form, which built the central concrete core to a height of 72 stories. This allowed the slip form to race ahead of schedule at a pace of 3 meters a day.
The second crane, which was another first, was a TC7 that was built off the side of the building starting at level 54. The base was placed on a diving-board-like structure tied back into the slab and anchored off of the floor below. This crane would ultimately climb to a height of 337m above the earth and dismantle TC1 and finish off the project. Not only was it successfully climbed up to over 100 stories in the air, but it was also taken down in record time with no problems.
As The Shard is the tallest building in Europe we would like to share our top three challenges associated with building such an iconic building.
Working with New Crane Designs
Any design engineers reading this will know first-hand the challenges with working with devices that have not fully been tested in the field. I mentioned before that we had two cranes being used for the very first time. The first thing you must always do is over-engineer. Safety is always the most important part of any construction process. Ask yourself what the worst-case scenario is and plan for that.
The second thing you should think about is what it is the crane must do. How will this new design benefit the construction site? What are the costs factored involved? Compare cost of production and preparation vs. saved man-hours on site. The last piece of the puzzle, but certainly not the least is that you must consider the life cycle of the crane. It is not enough just to know how you are going to install and climb these cranes—you also have to consider how you are going to get these cranes back down to the ground safely and limit the amount of impact this process has on the construction time schedule.
Wind and Dangerous Conditions
When your crane is over 300 meters in the air the primary safety concern is Mother Nature. Wind speeds and direction vary greatly at that altitude and it can be very unpredictable, especially in countries like England. Before you start work of any kind you must endure that wind speeds are at the appropriate levels as recommended by the manufacturer and the government.
Not only is the wind a major factor, but also the temperature. I can remember being on the slip form where TC1 was located at level 72 and engineers where shovelling snow on top to make room to lie rebar down, while below us it was raining cats and dogs. You’re not at sea level anymore so you will be open to these types of elements. A lot of the time we were working during the winter months and there is nothing worse than being stuck on a jib while the cold northern breeze blows through your bones. We had to make sure to dress accordingly each day, because it was a major factor tied to our performance; if you can’t feel the tools and materials with your fingers then you are more likely to drop something on an innocent worker below. Or if you are so cold you want to cut corners just to get down off the crane then you are more likely to become complacent and have an accident.
Building In a Busy Area
The Shard is located next to London Bridge, which also serves as the busiest railway station in the whole United Kingdom. This presented a whole new set of issues that we had to address, to not only ensure the safety of our technicians and fellow construction workers, but also the general public.
When working in the middle of a city centre at a height where you’re not easily noticed by people walking by, you have to think about how your work can impact them. Something as small as a falling nut or bolt can potentially kill someone.
There are a few tips I would recommend to anyone working in busy areas:
- Road closures: I would sooner give a person a headache by making them take a different direction home then to put their life at risk. Make sure you have all the proper paperwork in place with the local council, and you notify the public well in advance. If this is not an option then at the bare minimum erect a safety zone around the base of the crane extending at a 20m radius. This will ensure that if anything is dropped then no one will be hit by the impact.
- Tethering of Tools: When working with spanners and hammers at such a great height it is mandatory that you tie off the butt of the tool to your tool belt. This will stop the object from falling to the ground in the event you mistakenly drop it during any course of the construction process.
I hope that reading about our experience with working on such an elaborate project gives you more insight into the challenges of working on tower cranes. Have you faced similar challenges on a job site? Tell us about some of your experiences. If we can help you win and/or complete your next project, please contact me today.
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